Semiconductor devices are used in a large number of electronic devices, such as computers, cell phones, and others. Semiconductor devices are included in integrated circuits that are formed on semiconductor wafers by depositing many types of thin films of material over the semiconductor wafers, and patterning the thin films of material to form the integrated circuits. Semiconductor devices include field-effect transistors (FETs) such as metal oxide semiconductor (MOS) transistors.
A large amount of attention is given to addressing the deposition and patterning of the films to form the semiconductor devices on one side of the wafer. These devices are the functional components of an integrated circuit, and the device functionality in turn determines the functionality of the integrated circuit. Various techniques are used to form different structures using various materials for many different applications.
A relatively small amount of attention is given to addressing a side of the wafer on which the semiconductor devices are not formed. Generally, these semiconductor devices are formed on only one side of a wafer, and what is formed on another side has no impact on the functioning of those semiconductor devices. However, as discussed in detail below, the inventors have discovered that failing to address problems on the side of the wafer that devices are not formed can lead to a lower yield.